"This is the classic ‘forgetting curve’ by Ebbinghaus, a fundamental truth in memory theory, totally ignored by most educators and trainers. Most fixed ’courses’ or ‘lectures’ take no notice of the phenomenon, condemning much of their effort to the world of lost memories. Most educational and training pedagogies are hopelessly inefficient because they fail to recognise this basic truth. Smart learners get it. They revise over a period, with regular doses to consolidate their memories."